Containership

ABSTRACT

A containership includes a plurality of container-receiving cells each defined by a plurality of vertical guides extending from the tank top to a level adjacent the main deck hatch opening. Additional guides further extend upwardly from the below-deck guides to provide series of uninterrupted cells each accommodating a plurality of containers both below and above deck. Included are other above-deck guides to permit stowage to the skin of the ship. Hatch covers are provided having hinged end sections automatically operable during raising and lowering thereof within the above-deck guides to lock and unlock the covers at the main deck hatch coaming.

United States Patent 1191 Lunde et al. Aug. 6, 1974 [5 CONTAINERSHHP 3,583,350 6/1971 Goldman 114/72 [76] Inventors: Thomas Trygve Lunde, 6 Locksley Ave San Francisco, Calif 9 22; Primary ExaminerGeorge E. A. Halvosa Einar 0. Lunde, 66 Calypso Shores Assistant Examiner-Edward R. Kazenskc Novato, Calif 94947 Attorne Agent, or Firm-Emory L. Groff; Emory L.

Groff, Jr. [22] Filed: Apr. 21, 1972 [21] Appl. No.: 246,475 57 ABSTRACT A containership includes a plurality of container- Cl 114/201 l14/75 receiving cells each defined by a plurality of vertical [5 i 1 Int. guides extending from the tank top to a level adjacent Field of Search 73, 201 R, the main deck hatch opening. Additional guides furl 14/202; 214/15 R; 160/188 ther extend upwardly from the below-deck guides to provide series of uninterrupted cells each accommo- References Cited dating a plurality of containers both below and above UNITED STATES PATENTS deck. Included are other above-deck guides to permit 2,753,827 7/1956 Sabin 114 201 R stowage t0 the Skin of the P- Hatch Covers are P 3 380 422 4/1968 Bachko vided having hinged end sections automatically opera- 3,434,445 3/1969 Crumley ble during raising and lowering thereof within the 3,463,110 8/1969 Oshima above-deck guides to lock and unlock the covers at 3,465,807 9/1969 Boas the main deck hatch coaming 1494,486 2/1970 Knight et al. 3,552,345 1/1971 Harlander et al 114/72 14 Claims, 11 Drawing Figures PATENIEUws 61974 SHiH 1 [IF 4 SIEUZUF4 PATENTED 6W4 CONTAINERSHIP This invention relates generally to containerships, and more particularly to an improved construction providing for increased capacity for containers as well as a unique watertight hatch cover associated therewith.

The recent surge in popularity of containerships has already resulted in the development of many ship modifications, including the provision of relatively fixed vertically disposed guide means for permitting the ready loading and unloading of shipping containers which are normally stacked in multiple heights in adjacent cells with the lowermost container resting upon the tank top forming the inner bottom surface of the hold. Additionally, it is known to stow containers upon the main deck or main deck hatch covers.

By the present inventiona unique structure is provided wherein the containers may be continuously guided in an uninterrupted manner from the topmost portion of vertical cell guides disposed well above the main deck to a point below the main deck and extending all the way to the tank top. A novel hatch cover is associated with the present structure which cover may be positioned at the main deck coaming level to provide a locked watertight cover capable of supporting additional containers and/or other hatch covers. Alternatively, the hatch cover may be positioned at any vertical point within the same container cell guides above the main deck level.

The instant hatch cover included hinged portions at opposite ends thereof having alternate positions wherein in one such position the overall length of the hatch cover is foreshortened as gravity maintains the distal hinged portions in a lowered unlocked position, thereby permitting unimpeded vertical movement of the hatch cover within the cell guides. As the hatch cover is lowered into its desired position, either atop a previously loaded container, atop another hatch cover, or to the level of the main deck hatch opening, the hinged distal portions of the cover are automatically urged upwardly by the weight of the descending cover to an alternate position at which time the cover is fixedly locked. If the cover has been positioned at the main deck coaming level, means are further provided to automatically insure a watertight installation.

As a result of the present improvements, the multitude of loose gear and portable devices previously employed in securing the containers is now eliminated and the resultant savings in labor and material will be readily appreciated, particularly since such conventional accessories are very costly and have a short service life while also these prior devices require the services of stevedore lashing gangs.

A further advantage of the present invention is that the readily available shore-based or ship-based container cranes now in common use may be utilized to do all of the loading and unloading of the containers. as well as the hatch covers, without the necessity of any shipboard gangs, except for the dogging and undogging of the hatch covers.

By the present design of container cells above the main deck, it will be appreciated that improved lateral support is provided for the containers so that additive stresses imposed on the containers in heavy seas will be materially reduced. Thus, the container capacity may be appreciably increased.

Accordingly, one of the primary objects of the pres-. ent invention is to provide an improved containership including container cells extending from above the main deck to the tank top and providing for the continuous guidance of containers throughout the vertical extent of these cells.

Another object of the present invention is to provide an improved containership including vertical container guides extending from the tank top to a point adjacent the main deck hatch coaming and thereat aligned with additional guides extending well above main deck. Included are hatch covers movable to any vertical point between said uppermost guides and having automatically actuated means associated therewith for locking the covers in position.

A further object of the present invention is to provide an improved hatch cover for use in a containership and including hinged portions at opposite ends displaceable from a first position providing reduced overall length of the cover to a second position wherein the cover is urged into an extended locked condition.

Still another object of the present invention is to provide a hinged hatch cover for use in a containership including displaceable hinged portions at opposite ends thereof, which portions are provided with peripheral sealing means affording a watertight joint both with the remainder of the hatch cover, when in the locked con dition, as well as with the hatch coaming when disposed thereupon.

A further object of the present invention is to provide a containership having improved stowage capacity including increased stowage on deck. By means of unique vertical cell guides the necessity of fittings and lashings is obviated.

Another object of the present invention is to provide an improved hatch cover having hinged end portions for use with container cell guides provided with actuating means for automatically displacing the hinged portions from a lowered release position to a planar locked position.

With these and other objects in view which will more readily appear as the nature of the invention is better understood, the invention consists in the novel con,- struction, combination and arrangement of parts hereinafter more fully described, illustrated and claimed.

A preferred and practical embodiment of the present invention is shown in the accompanying drawings, in which:

FIG. 1 is a partial perspective view of a containership according to the present invention.

FIG. 2 is a top plan view of a hatch cover according to the present invention with the distal hinged portions shown in the locked position.

FIG. 3 is a side elevation of the hatch cover of FIG. 2 and illustrates the sequential movement of the hinged end portions between the alternate positions as the hatch cover is lowered into position atop the hatch coaming.

FIG. 4 is a partial side elevation of one end of a hatch cover as it would appear in the locked condition and disposed upon a planar supporting surface.

FIG. 5 is a view similar to FIG. 4 and illustrates the hatch cover as it would appear when locked and disposed atop the vertical cell guides.

FIG. 6 is a partial side elevation and illustrates one end of a hatch cover as it appears with the hinged portions in their alternative positions.

FIG. 7 is a partial vertical sectional view through one corner of a hatch cover with the hinge structure eliminated for purposes of clarity, and illustrates the transverse gasket joining the movable hinged end portion to the main body of the cover.

FIG. 8 is a top plan view of the structure of FIG. 7.

FIG. 9 is a vertical sectional view along the line 9-9 of FIG. 8, and illustrates both the transverse as well as the longitudinal gasket means associated with the hatch cover.

FIG. 10 is a sectional view along the line l-10 of FIG. 8, and illustrates the glued connection between the transverse and longitudinal gaskets.

FIG. 11 is a vertical sectional view taken along the line 1]ll I of FIG. 8, and illustrates the watertight seal provided by the longitudinal gasket mounted on the hatch cover and the gasket bar fixedly disposed upon the coaming.

Similar reference characters designate corresponding parts throughout the several figures of the drawings.

Referring now to the drawings, particularly FIG. 1, the present invention will be seen to relate to a containership, generally designated I, adapted for the stowage of a plurality of shipping containers C or C which are stacked in a plurality of tiers 2 extending upwardly from the tank top 3 to a selected point above the main deck 4.

The general stowage of the containers will initially be described. By the present invention either of the two most standard sizes of containers may be readily stowed within the containership without any modifica tion of the tier arrangement. The tiers of containers are adapted to be freely lowered and raised between a plurality of vertical cell guides G. These guides are positioned at the four corners designating each vertical cell and will be seen to comprise a guide 5 utilized at each' corner of each hold and a T-shaped cell guide 6 which is used intermediate each pair of adjacent corner guides 5.

A feature of the present invention is the provision for the continuous guidance of all containers from the topmost portion of the guides through the main deck opening to the bottom supporting surface of the tank top 3. These cell guides are preferably interrupted at the main deck 4 so that the installation and removal of the unique watertight hatch cover of the present invention may be accommodated as will be described hereinafter.

Sufficient structural components are included above the main deck 4 to provide adequate lateral stability for the cell guide members extending above the limits of the ships hull 7 such as the diagonal stays 8. Additionally, the uppermost limits of each of the cell guides are preferably flared outwardly as at 9 to facilitate the guidance therebetween of both the containers C and C as well as the hatch covers. By arranging the fore and aft clearance between opposed vertical cell guides G to provide the proper distance for the acceptance of standard 40-foot containers, it will be appreciated that each hold may also accommodate two longitudinally aligned 20-foot containers in the same space which would nor- FIG. 1, turn-lock type adapter cones 10 are utilized to interlock the top and bottom faces of vertically adjacent 20-foot containers which may be stowed throughout the entire vertical extent of a cell or may be alternately stowed with the larger containers C. Appropriate securing means should be used between the opposed end faces of the smaller containers C such as any well known bridge fittings (not shown) and diagonal stays. When both sizes of containers are being stowed aboard any single containership 1, it will be quite apparent that a single container C may quite conveniently be positioned as the uppermost container in each cell, thus serving as a cap for two smaller containers C immediately therebeneath.

The hatch cover 11 utilized in combination with the present invention is shown in its entirety in FIG. 2 of the drawings. Each hatch cover comprises a main body portion 12 having a transverse dimension which will be understood to be fixed and spans the lateral distance between the confined portions of two adjacent vertical cell guides. The planar main body portion 12 includes a pair of oppositely disposed terminal portions 13-13 each of which is associated with a distal hinged section, generally designated 14. Each hinged section 14 includes a pair of corner plates 15 joined together by a central web 16 underlying the main body terminal portion 13. As will be seen particularly in FIGS. 2 and 3, the upper surface 13a of each terminal portion is coplanar with the adjacent upper surface 12a of the main body portion 12 while the lower surface 13b of each terminal portion is elevated with respect to the remainder of the hatch cover to accommodate the underlying central webl6 of the hinged sections 14 when in the locked position as shown in the lower portions of FIG. 3. Additionally, the end wall 16a of each hinged section will be seen to project beyond the end wall of the adjacent terminal portion 13 when the hinged sections are elevated to the locked position.

Any suitable type of hinge connection 17 may be utilized to pivotally connect each section 14 to the main body portion 12 so as to permit pivotal displacement of the hinged sections to and from the unlocked position as shown in the upper portion of FIG. 3 of the drawings. It will be readily appreciated that, when the hinged sections are in this unlocked position, the overall longitudinal length of the hatch cover 11 is reduced, while movement of these sections to the position shown in the lower portion of FIG. 3 or in the position of FIG. 2 will provide an extended length to the hatch cover, a length which will be understood to exceed the longitudinal distance between the inner faces of two op posed cell guides.

Means are provided in connection with the vertical cell guides G as well as with each hatch cover 11 to automatically regulate the displacement of the hinged sections 14 of the hatch cover during its insertion and removal within the confines of any cell 2 of the containership as defined by the plurality of guides associated with each cell.

A suitable latch L may be provided at each end of the hatch cover to retain the hinged sections 14in the planar locked position to facilitate storage, shipping or other handling of the hatch covers. In use, the latches L are opened and the same lifting spreader (not shown) as used to handle the containers C, C is connected to suitable attachments A preferably flush-mounted in the upper surface 12a. Upon lifting of the main body portion of the hatch cover, the two hinged sections 14 will assume the lowered position due to gravity with a resultant shortening of the hatch cover length. At this stage, the end walls 13c of the two terminal portions 13 will just clear the inner surfaces of the opposed guides 5 and 6 of the cell 2. A centerline guide G is fixedly disposed at each end of each cell and is received by a notch n centrally formed in the end wall 130 of each terminal portion 13.

The downward displacement of each corner plate is limited by means of the bracket 18 having its opposite portions pivotally attached to the hatch cover terminal portion 13 at point 19 and to the corner plate 15 at point 20, respectively. The intermediate position of the hatch cover shown in FIG. 6 illustrates the unlocked position of the hatch cover wherein it will be seen that the hinged section 14 is fully displaced, by gravity, into a downward position about the hinge 17 with its displaced angle being limited by the bracket 18. It will be appreciated that the bracket 18 should be of a type which, when extended as in this portion of FIG. 6, includes a central pivot 21 disposed short of the centerline connecting the pivot points 19 and 20 for reasons which will become obvious hereinafter.

The hatch cover may be lowered to any vertical point within any cell above the main deck level until the lowermost point thereof, namely the rubber covered rollers 22, engage a stationary object which may be the top surface of a container C or C, or the top surface of another hatch cover, as shown in this figure of the drawings. Mounted upon each corner plate 15 is a roller assembly generally designated 23 and which includes a compression cylinder 24 pivotally attached at its free end as at 25 and from which extends from its opposite end an actuating rod 26. The distal portion of the rod 26 will be seen to be pivotally connected to one end of a crank 27, which crank is pivotally supported upon the undersurface of the corner plate 15 as at 28, while the opposite free end of the crank rotatably supports the rubber covered roller 22. Any suitable resilient means may be employed within the compression cylinder 24 to normally maintain the actuating rod 26 in an extended position so that the crank 27 and roller 22 will appear as shown in the upper portion of FIG. 6. It will be noted that when in this position the lower periphery of the roller 22 is disposed in a lower plane than any other portion of the structure of the hatch cover so that it is this roller which would be the first element to engage any horizontal planar structure located beneath the hatch cover as it is lowered within a cell. The biasing force of the compression cylinder 24 is selected to insure extension of the actuating rod 26 when the roller 22 is supporting only the weight of the hinged sections 14 but is such that when the weight of the entire hatch cover is being supported by the rollers, will permit collapse of the rod 26 to allow pivoting of the roller to the position as shown in FIG. 4. In the bottom portion of FIG. 6, a first hatch cover is shown disposed in the locked condition upon the hatch opening at the main deck 4 and the intermediate hatch cover located thereabove, has been lowered until the roller 22 engages the top surface of the locked hatch cover. Continued lowering of the intermediate hatch cover causes, by gravity, the mass of the main body portion 12 of the hatch cover to pivotally displace the hinged section 14 in an upward direction. This action occurs until the bevel surface 29 on the outer edge 16a of the hinged section abuts the vertical cell guide G, thus halting any further downward movement of this hatch cover. From the foregoing, it will be seen that provision is made for the stowage of an unused hatch cover wherein it has been positioned upon the top of another hatch cover which is in locked condition over the hatch opening of the main deck.

The principal use of the hatch covers 11 will, of course, involve the use of these covers to seal the access to the cells or tiers 2 located within the ships hold and in this regard it will be understood that means must be provided to enable passage of the hatch covers 11 through the above deck cell guides to the level of the main deck hatch opening. FIG. 5 of the drawings and the lower portion of both FIG. 3 and FIG. 6 illustrate the structure of the hatch cover as it appears immediately prior to the final lowering of the cover into position upon the hatch coaming.

As the cover is lowered through the above deck vertical cell guide members the hinged end sections 14 at the two opposite ends of the cover will be disposed in the lowered, depending position as shown in FIGS. 3 and 6 and as the cover is guided through the cell guides it is maintained in axial alignment therethrough by means of the centerline fixed guide element G which is being engaged by the notch n in the distal surface of the terminal portion 13 of the main body section 12. Each hinged end section 14 is provided at its two opposite corners with a fixed support element or wheel 30 which is mounted by any suitable means upon the end wall 16a of the hinged section and includes an axle (not shown) arranged to position each fixed support wheel 30 in a plane outside of or beyond the sides of each end section 14 so that there will be no interference between the vertical cell guide members and this wheel as the hatch cover is lowered with the end sections in their depending position.

Disposed slightly above and outside of the vertical plane of the main hold cell guide members is a fixed rail 31 which will be seen in FIG. 6 to be located immediately in the path of the fixed support element 30 as the hatch cover is being lowered in its foreshortened condition. Thus each wheel 30 will engage the planar portion of the fixed rail 31 as the cover approaches the hatch coaming level, and further lowering of the hatch cover will urge the hinged end sections to be displaced upwardly towards a position coplanar with the remainder of the hatch cover. At this point the fixed wheels 30 are guided beyond the terminal portions 32 of their respective fixed rails 30 and onto a coplanar spring-loaded platform 33 disposed adjacent the fixed rail terminal portion 32. It will be understood that each pair of platforms 33 are regulated so as to support, without deflection, the full weight of the respective end section 14 itself so that, at the instant the structure achieves the position shown in he lower part of FIG. 6, the springloaded platforms 33 will be supporting only the weight of the respective hinged section 14. However, as the hatch cover is further lowered, the full weight of the hatch cover will be supported by the platforms 33 which then are deflected downwardly by this increased weight until the gasket 39 carried by the hatch cover rests upon the gasket bar 37 projecting upwardly from the coaming.

Quite obviously, appropriate sealing means must be provided between both the hatch cover and the coaming as well as between the relatively movable components comprising the hatch cover itself. As shown in FIGS. 8ll of the drawings, the juncture between each end section 14 and the main body portion l2of the hatch cover is sealed on its lower surface juxtaposed the hinge 17 by means of a transverse gasket 35 comprising a longitudinal strip of relatively flexible material having its two edges suitably attached to the main body portion and end section, respectively, such as by the fasteners 36. Additional sealing means are provided about the peripheral edges of both the hinged sections and main body portion adapted to engage an upstanding gasket bar 37 projecting from the top of the coaming 38. This latter means comprises a longitudinal gasket 39 suitably attached to the bottom surface of both the main body portion and hinged sections adjacent the outer edges thereof. In the area of the outer edge of the transverse gasket 35 where the two gasket components 35 and 39 intersect, it will be seen that a watertight arrangement may be provided by recessing the gasket 35 within the lower face of the respective longitudinal gaskets 39, as shown in FIG. 10, so that a coplanar sealing surface will be achieved.

To insure accurate spotting of the hatch cover 11 during movement into position upon the coaming 38, a plurality of fixed guide posts 38 are provided at the coaming level along each side of each cell as shown in FIG. 2.

What is claimed is:

l. in a containership having a hold within the hull of the ship extending between a main deck provided with a hatch opening and a tank top adjacent the bottom of the hull, the combination comprising; a plurality of vertically disposed cell guide members within said hold extending from the bottom thereof to a point adjacent said main deck hatch opening, said guide members disposed to provide below said main deck a plurality of vertically extending and adjacent cells of rectangular configuration each adapted to receive a plurality of containers in stacked relationship, coaming at said main deck level adjacent said hatch opening, additional cell guide members fixedly mounted above said main deck and providing a plurality of adjacent cells vertically aligned with said cells within said hold whereby a continuous cell is provided by each pair of respective above and below main deck cells, a unitary hatch cover assembly adapted to be selectively lowered to any level within any one of said cells above said main deck, atop any one of said cells at said main deck level or on top of a container within any one of said above main deck cells, said cover assembly including a rigid planar main body section spanning the majority of the axial length of one said cell, an end section attached to each distal portion of said main body section, means pivotally connecting each said end section to said main body section to permit displacement of said end sections between a horizontal position coplanar with said main body section and a lowered depending position, said end sections when in said horizontal position providing an axial length to said hatch cover assembly in excess of the axial length of one said cell whereby said end sections may be disposed upon said coaming and when said end sections are lowered to said depending position the axial length of said hatch cover assembly is foreshortened and the hatch cover may be lowered or raised as a unitary assembly within the confines of one said above main deck cell.

2. A containership according to claim 1 wherein, said hatch cover assembly when said end sections are in said horizontal position may serve as a base to alternately support either a single full length container or a pair of halflength containers disposed end-to-end upon said hatch cover and said hatch cover includes fittings engageable with the bottoms of a pair of said half-length containers at points adjacent the juxtaposed ends thereof.

3. A containership according to claim 1 wherein, said cell guide members in said hold and above said main deck are interrupted adjacent the level of said hatch opening.

4. A containership according to claim 1 wherein, each axial end of said hatch cover main body section includes an integral terminal portion having an end wall provided with a notch, and a fixed vertical guide element disposed at opposite ends of each said cell and engageable within said notches to maintain longitudinal and lateral alignment of said hatch cover during lowering and raising within said cells.

5. A containership according to claim 1 including, latch components on said hatch cover assembly selectively operable to lock at least one said end section to said main body section when coplanar therewith.

6. A containership according to claim 1 including, transverse flexible gasket means between said pivotally connected end sections and said main body section, longitudinal gasket means on the undersurface of said end sections and main body section, and means on said coaming engageable with said longitudinal gasket means to provide a watertight seal about the periphery of said hatch cover assembly.

7. A containership according to claim 1 wherein, each end of said hatch cover main body section includes a medially disposed terminal portion integral with said main body section and axially extending therebeyond, each said end section including a pair of corner plates disposed on either side of each said terminal portion and a central web joins said corner plates and underlies said terminal portion.

8. A containership according to claim 1 wherein, each said end section pivotal connecting means includes a hinge, means defining the lowermost limit of said depending position of said end sections, a roller assembly carried by each said end section, each said roller assembly including a displaceable roller disposed below said end section and means in said roller assembly normally maintaining said roller in a downward position in a plane lower than any part of said hatch cover when no portion of the weight of said main body section is applied to said roller and said end sections are in the lowered depending position.

9. A containership according to claim 8 wherein, said roller is carried by one end of a pivotal crank, said maintaining means including a compression cylinder, an actuating rod extending from said cylinder and engaging the opposite end of said crank whereby, said rod remains fully extended and said roller is in its downwardmost position until said end section is pivotally displaced to said horizontal position and the weight of said main body section acts on said cylinder.

10. A containership according to claim 5 wherein, said limit means includes a bracket having its opposite ends pivotally attached respectively to said main body section and said end section whereby an acute angle is formed between said end section and main body section when said bracket is extended and said end section is in the depending position.

11. A containership according ,to claim 1 wherein, each said end section includes a fixedly attached support element extending laterally beyond the area of one said cell, a rail mounted above said main deck and vertically aligned with each said support element when said end sections are in the lowered depending position whereby, when said hatch cover is lowered to the level of said main deck said support elements engage said rails and the weight of said main body section urges said end sections to move from the lowered position to a horizontal position as said support elements slide over said rails.

12. A containership according to claim 11 wherein, said support element comprises a wheel.

13. A containership according to claim 11 including, a terminal portion on each said rail, a spring-loaded platform adjacent said terminal portion, said platform non-yielding under the weight of said end section but yielding under the full weight of said hatch cover assembly whereby said hatch cover assembly is lowered by gravity to engage said coaming.

14. A containership provided with a hull including a hold having upper and lower limits defined by a main deck hatch opening and a tank top, respectively, the lateral extent of said hold and hatch opening being substantially less than the beam of said containership, a first group of a plurality of fixed guide members extending upwardly from said tank top to said hatch opening to define cells below said main deck hatch opening each for the stowage of a plurality of containers stacked directly upon one another, a second group of a plurality of fixed guide members each extending upwardly from a point juxtaposed the upper limits of said first group of guide members to define cells above said main deck hatch opening each for the stowage of a plurality of containers stacked directly upon one another, each said cell defined above said main deck hatch opening being vertically aligned with one of said cells defined below said main deck hatch opening to define a continuous uninterrupted cell open at the top of said second group of guide members and extending to said tank top, a third group of a plurality of fixed guide members extending upwardly above the level of said main deck hatch opening and intermediate said second group of guide members and the beam of said hull to define additional cells above the level of said main deck hatch opening each for the stowage of a plurality of containers stacked directly upon one another, and hatch cover means insertable through each said cell defined by said second group of guide members to close the upper limit of each said cell defined by said first group of guide members at said main deck hatch opening. a 

1. In a containership having a hold within the hull of the ship extending between a main deck provided with a hatch opening and a tank top adjacent the bottom of the hull, the combination comprising; a plurality of vertically disposed cell guide members within said hold extending from the bottom thereof to a point adjacent said main deck hatch opening, said guide members disposed to provide below said main deck a plurality of vertiCally extending and adjacent cells of rectangular configuration each adapted to receive a plurality of containers in stacked relationship, coaming at said main deck level adjacent said hatch opening, additional cell guide members fixedly mounted above said main deck and providing a plurality of adjacent cells vertically aligned with said cells within said hold whereby a continuous cell is provided by each pair of respective above and below main deck cells, a unitary hatch cover assembly adapted to be selectively lowered to any level within any one of said cells above said main deck, atop any one of said cells at said main deck level or on top of a container within any one of said above main deck cells, said cover assembly including a rigid planar main body section spanning the majority of the axial length of one said cell, an end section attached to each distal portion of said main body section, means pivotally connecting each said end section to said main body section to permit displacement of said end sections between a horizontal position coplanar with said main body section and a lowered depending position, said end sections when in said horizontal position providing an axial length to said hatch cover assembly in excess of the axial length of one said cell whereby said end sections may be disposed upon said coaming and when said end sections are lowered to said depending position the axial length of said hatch cover assembly is foreshortened and the hatch cover may be lowered or raised as a unitary assembly within the confines of one said above main deck cell.
 2. A containership according to claim 1 wherein, said hatch cover assembly when said end sections are in said horizontal position may serve as a base to alternately support either a single full length container or a pair of halflength containers disposed end-to-end upon said hatch cover and said hatch cover includes fittings engageable with the bottoms of a pair of said half-length containers at points adjacent the juxtaposed ends thereof.
 3. A containership according to claim 1 wherein, said cell guide members in said hold and above said main deck are interrupted adjacent the level of said hatch opening.
 4. A containership according to claim 1 wherein, each axial end of said hatch cover main body section includes an integral terminal portion having an end wall provided with a notch, and a fixed vertical guide element disposed at opposite ends of each said cell and engageable within said notches to maintain longitudinal and lateral alignment of said hatch cover during lowering and raising within said cells.
 5. A containership according to claim 1 including, latch components on said hatch cover assembly selectively operable to lock at least one said end section to said main body section when coplanar therewith.
 6. A containership according to claim 1 including, transverse flexible gasket means between said pivotally connected end sections and said main body section, longitudinal gasket means on the undersurface of said end sections and main body section, and means on said coaming engageable with said longitudinal gasket means to provide a watertight seal about the periphery of said hatch cover assembly.
 7. A containership according to claim 1 wherein, each end of said hatch cover main body section includes a medially disposed terminal portion integral with said main body section and axially extending therebeyond, each said end section including a pair of corner plates disposed on either side of each said terminal portion and a central web joins said corner plates and underlies said terminal portion.
 8. A containership according to claim 1 wherein, each said end section pivotal connecting means includes a hinge, means defining the lowermost limit of said depending position of said end sections, a roller assembly carried by each said end section, each said roller assembly including a displaceable roller disposed below said end section and means in said roller assembly normally maintaining Said roller in a downward position in a plane lower than any part of said hatch cover when no portion of the weight of said main body section is applied to said roller and said end sections are in the lowered depending position.
 9. A containership according to claim 8 wherein, said roller is carried by one end of a pivotal crank, said maintaining means including a compression cylinder, an actuating rod extending from said cylinder and engaging the opposite end of said crank whereby, said rod remains fully extended and said roller is in its downwardmost position until said end section is pivotally displaced to said horizontal position and the weight of said main body section acts on said cylinder.
 10. A containership according to claim 5 wherein, said limit means includes a bracket having its opposite ends pivotally attached respectively to said main body section and said end section whereby an acute angle is formed between said end section and main body section when said bracket is extended and said end section is in the depending position.
 11. A containership according to claim 1 wherein, each said end section includes a fixedly attached support element extending laterally beyond the area of one said cell, a rail mounted above said main deck and vertically aligned with each said support element when said end sections are in the lowered depending position whereby, when said hatch cover is lowered to the level of said main deck said support elements engage said rails and the weight of said main body section urges said end sections to move from the lowered position to a horizontal position as said support elements slide over said rails.
 12. A containership according to claim 11 wherein, said support element comprises a wheel.
 13. A containership according to claim 11 including, a terminal portion on each said rail, a spring-loaded platform adjacent said terminal portion, said platform non-yielding under the weight of said end section but yielding under the full weight of said hatch cover assembly whereby said hatch cover assembly is lowered by gravity to engage said coaming.
 14. A containership provided with a hull including a hold having upper and lower limits defined by a main deck hatch opening and a tank top, respectively, the lateral extent of said hold and hatch opening being substantially less than the beam of said containership, a first group of a plurality of fixed guide members extending upwardly from said tank top to said hatch opening to define cells below said main deck hatch opening each for the stowage of a plurality of containers stacked directly upon one another, a second group of a plurality of fixed guide members each extending upwardly from a point juxtaposed the upper limits of said first group of guide members to define cells above said main deck hatch opening each for the stowage of a plurality of containers stacked directly upon one another, each said cell defined above said main deck hatch opening being vertically aligned with one of said cells defined below said main deck hatch opening to define a continuous uninterrupted cell open at the top of said second group of guide members and extending to said tank top, a third group of a plurality of fixed guide members extending upwardly above the level of said main deck hatch opening and intermediate said second group of guide members and the beam of said hull to define additional cells above the level of said main deck hatch opening each for the stowage of a plurality of containers stacked directly upon one another, and hatch cover means insertable through each said cell defined by said second group of guide members to close the upper limit of each said cell defined by said first group of guide members at said main deck hatch opening. 